Method and storage medium for replacing process instrument in processing apparatus

ABSTRACT

Disclosed is a method for replacing a process instrument in a processing apparatus, in which a target object is loaded by a transfer mechanism into a processing unit and is subjected to a process by use of the process instrument. The method includes confirming that a process on the target object is finished in a processing unit designated as a process instrument replacement target, and providing information that a process instrument replacing operation is permitted to start. The method further includes, when a shutter of the processing unit designated as the process instrument replacement target is closed to perform a process instrument replacing operation and an operation prohibition state is thereby applied to the transfer mechanism, canceling the operation prohibition state to allow the transfer mechanism to perform a load/unload operation relative to a processing unit not designated as a process instrument replacement target.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for replacing a processinstrument in a processing apparatus used for processing a targetobject, such as a semiconductor wafer, and a storage medium that storesa program for replacement.

2. Description of the Related Art

In general, in the steps for manufacturing semiconductor devices or thelike, a photolithography technique is utilized to form a resist patternon the surface of a substrate to be processed (which will be referred toas a target object), such as a semiconductor wafer or LCD substrate.This photolithography technique includes a resist coating process forapplying a resist liquid onto the surface of the target object; a lightexposure process for subjecting the resist film thus formed to lightexposure with a circuit pattern; and a developing process for supplyinga developing solution onto the target object treated by the lightexposure process. These processes are performed by use of acoating/developing apparatus.

In general, a coating/developing apparatus includes a carry-in sectionand a carry-out section for transferring target objects into and out ofthe apparatus; processing units for performing processes of varioustypes, such as the resist coating process, light exposure process, anddeveloping process, described above; and an interface section fortransferring target objects between these areas. The interface sectionincludes transfer means, such as a transfer arm, by which target objectsare sequentially transferred from the carry-in section to selected onesof the processing units. Each of the processing units has a transferport provided with a shutter, through which a target object is loadedinto the processing unit. The target object thus loaded is subjected toa process, such as the coating process, in the processing unit.Thereafter, the processed target object is transferred by the transfermeans to another processing unit or the carry-out section.

Each of the processing units has an opening provided with a cover dooron the side (outer side) opposite to the transfer port provided with theshutter. Where a maintenance operation is performed on each of theprocessing units, the cover door of the opening is opened by anoperator. When the cover door is opened, an interlock mechanism isactivated to stop the entire operation of the coating/developingapparatus, thereby satisfying a safety standard.

For example, a coating unit includes a spin chuck located therein forholding a target object or substrate, and a process cup serving as aprocess instrument for surrounding the spin chuck and target object. Aprocess liquid is supplied onto the surface of the substrate set in astate described above, while the substrate is being rotated. Currently,the process cup needs to be replaced twice a week. When the cover doorof the coating unit is opened to perform this cup replacing operation inthe middle of processes, the interlock mechanism is activated to stopthe transfer means or transfer mechanism. In light of this,conventionally, the process cup replacing operation is performed afterthe light exposure process and developing process in processing unitsare finished and all the target objects are collected into a carrier.

However, while the interlock mechanism is in an activated state formaintenance of one of the processing units, the coating/developingapparatus is entirely stopped until the maintenance is finished. Thismeans that the operation rate of the apparatus is decreased.

In light of this, there is proposed a substrate processing apparatus toimprove the apparatus operation rate (for example, see Jpn. Pat. Appln.KOKAI Publication No. 2006-12912). According to this apparatus, aninterlock mechanism is set disabled on the condition that the shutter ofthe transfer port of a processing unit is closed by an operator. Thismakes it possible to prevent the processing apparatus from beingundesirably entirely stopped when the cover door is opened.

However, depending on the type of a processing unit, unsolved problemsremain when an operator simply closes the shutter by a switchingoperation to set the interlock mechanism disabled.

For example, where a processing apparatus includes only one coating unitas a whole, a replacing operation of the process cup of this coatingunit brings about a state where no usable coating unit is present in theapparatus. In this case, it is necessary to set takeoff suspension ofthe next lot and/or to stop the processing apparatus entirely. Further,even where a processing apparatus includes a plurality of coating units,the program needs to be modified to bypass the processing unitdesignated as a cup replacement target.

Further, where a cup replacing operation is performed on a coating unit,it is preferable that the process cup can be replaced immediately afterthe process in the coating unit is finished. However, the conventionaltechnique is arranged such that an operator closes the shutter of thetransfer port of an objective processing unit by a switching operation,without an automatic judgment as to whether the process in theprocessing unit is finished. In this case, the operator is required tomake a judgment as to when the shutter should be closed while processesare sequentially performed. Accordingly, a time delay tends to be causedafter the process in the processing unit is finished and before theshutter is closed and the cover door is opened.

Such a problem may be also caused in replacement or inspection ofanother process instrument that constitutes a processing unit, such as anozzle or spin chuck, besides a process cup.

BRIEF SUMMARY OF THE INVENTION

An object of the present invention to provide a method for replacing aprocess instrument and a storage medium that stores a program forreplacement. This method allows a process instrument, such as a processcup, to be replaced, while a process is continued in a processing unitincluding a process instrument not designated as a replacement target.Further, this method allows the next lot to be continuously processed bya processing unit of the same type including no process instrument to bereplaced.

According to a first aspect of the present invention, there is provideda method for replacing a process instrument in a processing apparatus,in which an target object is loaded by transfer means into a processingunit and is subjected to a process by use of the process instrument, themethod comprising: confirming that a process on the target object isfinished in a processing unit designated as a process instrumentreplacement target, and providing information that a process instrumentreplacing operation is permitted to start; and, when a shutter of theprocessing unit designated as the process instrument replacement targetis closed to perform a process instrument replacing operation and anoperation prohibition state is thereby applied to the transfer means,canceling the operation prohibition state to allow the transfer means toperform a load/unload operation relative to a processing unit notdesignated as a process instrument replacement target.

According to a second aspect of the present invention, there is provideda method for replacing a process instrument in a processing apparatus,in which a target object from a carry-in section is sequentially loadedby transfer means into some of a plurality of processing units toperform a process thereon, and the target object thus processed isunloaded by the transfer means to a carry-out section, wherein theprocessing units comprise a processing unit that includes a processinstrument and is configured to perform a process on the target objectby use of the process instrument, the method comprising: setting anappointment for a process instrument replacement target; setting takeoffsuspension of a next lot from the carry-in section, in response to theappointment being set, before staring a process instrument replacingoperation; confirming that a process on the target object is finished ina processing unit designated as the process instrument replacementtarget, and providing information that a process instrument replacingoperation is permitted to start; when a shutter of the processing unitdesignated as the process instrument replacement target is closed toperform a process instrument replacing operation and an operationprohibition state is thereby applied to the transfer means, cancelingthe operation prohibition state to allow the transfer means to perform aload/unload operation relative to a processing unit not designated as aprocess instrument replacement target; and canceling the takeoffsuspension of the next lot from the carry-in section, in response to aprocess instrument replacing operation being finished.

According to a third aspect of the present invention, there is provideda method for replacing a process instrument in a processing apparatus,in which a target object from a carry-in section is sequentially loadedby transfer means into some of a plurality of processing units toperform a process thereon, and the target object thus processed isunloaded by the transfer means to a carry-out section, wherein theprocessing units comprise processing units of the same type thatincludes a process instrument and is configured to perform a process onthe target object by use of the process instrument, the methodcomprising: setting an appointment for a process instrument replacementtarget; confirming that a process instrument in one of the processingunits of the same type is to be replaced, and changing a transferschedule for transferring the target object, preset prior to theappointment, into a transfer schedule arranged to avoid use of aprocessing unit designated as the process instrument replacement target;confirming that a process on the target object is finished in theprocessing unit designated as the process instrument replacement target,and providing information that a process instrument replacing operationis permitted to start; and, when a shutter of the processing unitdesignated as the process instrument replacement target is closed toperform a process instrument replacing operation and an operationprohibition state is thereby applied to the transfer means, cancelingthe operation prohibition state to allow the transfer means to perform aload/unload operation relative to a processing unit not designated as aprocess instrument replacement target.

According to a fourth aspect of the present invention, there is provideda storage medium that stores a program for execution on a computer toreplace a process instrument in a processing apparatus, in which antarget object is loaded by transfer means into a processing unit and issubjected to a process by use of the process instrument, wherein theprogram causes the computer to execute: confirming that a process on thetarget object is finished in a processing unit designated as a processinstrument replacement target, and providing information that a processinstrument replacing operation is permitted to start; and, when ashutter of the processing unit designated as the process instrumentreplacement target is closed to perform a process instrument replacingoperation and an operation prohibition state is thereby applied to thetransfer means, canceling the operation prohibition state to allow thetransfer means to perform a load/unload operation relative to aprocessing unit not designated as a process instrument replacementtarget.

According to a fifth aspect of the present invention, there is provideda storage medium that stores a program for execution on a computer toreplace a process instrument in a processing apparatus, in which atarget object from a carry-in section is sequentially loaded by transfermeans into some of a plurality of processing units to perform a processthereon, and the target object thus processed is unloaded by thetransfer means to a carry-out section, wherein the processing unitscomprise a processing unit that includes a process instrument and isconfigured to perform a process on the target object by use of theprocess instrument, and wherein the program causes the computer toexecute: setting an appointment for a process instrument replacementtarget; setting takeoff suspension of a next lot from the carry-insection, in response to the appointment being set, before staring aprocess instrument replacing operation; confirming that a process on thetarget object is finished in a processing unit designated as the processinstrument replacement target, and providing information that a processinstrument replacing operation is permitted to start; when a shutter ofthe processing unit designated as the process instrument replacementtarget is closed to perform a process instrument replacing operation andan operation prohibition state is thereby applied to the transfer means,canceling the operation prohibition state to allow the transfer means toperform a load/unload operation relative to a processing unit notdesignated as a process instrument replacement target; and canceling thetakeoff suspension of the next lot from the carry-in section, inresponse to a process instrument replacing operation being finished.

According to a sixth aspect of the present invention, there is provideda storage medium that stores a program for execution on a computer toreplace a process instrument in a processing apparatus, in which atarget object from a carry-in section is sequentially loaded by transfermeans into some of a plurality of processing units to perform a processthereon, and the target object thus processed is unloaded by thetransfer means to a carry-out section, wherein the processing unitscomprise processing units of the same type that includes a processinstrument and is configured to perform a process on the target objectby use of the process instrument, and wherein the program causes thecomputer to execute: setting an appointment for a process instrumentreplacement target; confirming that a process instrument in one of theprocessing units of the same type is to be replaced, and changing atransfer schedule for transferring the target object, preset prior tothe appointment, into a transfer schedule arranged to avoid use of aprocessing unit designated as the process instrument replacement target;confirming that a process on the target object is finished in theprocessing unit designated as the process instrument replacement target,and providing information that a process instrument replacing operationis permitted to start; and, when a shutter of the processing unitdesignated as the process instrument replacement target is closed toperform a process instrument replacing operation and an operationprohibition state is thereby applied to the transfer means, cancelingthe operation prohibition state to allow the transfer means to perform aload/unload operation relative to a processing unit not designated as aprocess instrument replacement target.

According to the first and fourth aspects of the present invention, aoperation prohibition state applied to the transfer means is cancelled,so as to allow the transfer means to perform a load/unload operationrelative to a processing unit not designated as a process instrumentreplacement target, on the two conditions that a process on the targetobject is finished in a processing unit designated as the processinstrument replacement target, and a shutter of the processing unitdesignated as the process instrument replacement target is closed.Consequently, it is possible to replace the process instrument moresafely and rapidly, as compared to a case where the shutter is closed byan operator's switching operation.

According to the second and fifth aspects of the present invention,takeoff suspension of the next lot from the carry-in section is setbefore a process instrument replacing operation is started.Consequently, even where there is no alternative processing unit of thesame type as the processing unit designated as the process instrumentreplacement target, it is possible to prevent a process from beingunnecessarily performed in a processing unit other than the processinstrument replacement target.

According to the third and sixth aspects of the present invention, wherea process instrument is replaced at only one of a plurality ofprocessing units of the same type, the transfer schedule is changed tocontinue a process by use of another processing unit, which is notdesignated as a process instrument replacement target, but of the sametype as the processing unit designated as the process instrumentreplacement target. Consequently, it is possible to continue processeswithout extremely decreasing the operation rate of the entire processingapparatus.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a plan view schematically showing an example of a resistliquid coating/developing system, to which a method for replacing aprocess cup according to the present invention can be applied;

FIG. 2 is a front view schematically showing the resist liquidcoating/developing system;

FIG. 3 is a back view schematically showing the resist liquidcoating/developing system;

FIG. 4 is a view showing the structure of a coating unit used in theresist liquid coating/developing system;

FIG. 5 is a flowchart showing a method for replacing a process cupaccording to the present invention; and

FIGS. 6 to 8 are views constituting a flowchart showing a specificexample of a method for replacing a process cup according to the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

An embodiment of the present invention will now be described withreference to the accompanying drawings. In this embodiment, the presentinvention is applied to a method for replacing a process cup in a resistliquid coating/developing system for semiconductor wafers.

FIG. 1 is a plan view schematically showing a resist liquidcoating/developing system according to this embodiment. FIG. 2 is afront view of the system shown FIG. 1. FIG. 3 is a back view of thesystem shown FIG. 1.

The resist liquid coating/developing system comprises a cassette station10, a process station 20, and an interface section 30, as the mainsections. The cassette station 10 serves as a carry-in section and acarry-out section such that wafer cassettes 1 are transferredtherethrough from the outside to this system and from this system to theoutside. Each of the wafer cassettes 1 stores a plurality of, e.g., 25,target objects or semiconductor wafers W (which will be referred to aswafers W). Further, the cassette station 10 is used to transfer wafers Wto and from the wafer cassettes 1. The process station 20 includes aprocessing apparatus main body formed of a plurality of processing unitsof various types stacked each other at predetermined positions. Each ofthe processing units is configured to perform a predetermined process onwafers W one by one during coating and developing processes. Theinterface section 30 is used to transfer wafers W between the processstation 20 and a light exposure apparatus (not shown) located adjacentthereto.

As shown in FIG. 1, the cassette station 10 includes a cassette table 2for placing wafer cassettes 1 thereon. The cassette station 10 isprovided with a plurality of, e.g., four, projections 3, so that thewafer cassettes 1 are placed in a row in a horizontal X-direction atpositions set by the projections 3 while their wafer port openings aredirected toward the process station 20. The cassette station 10 includesa wafer transfer arm 4, which is movable in the cassette array direction(X-direction) and the array direction of wafers W (Z-direction) storedand stacked in each cassette 1 in the vertical direction. Accordingly,the wafer transfer arm 4 can selectively transfer wafers W to and fromany one of the wafer cassettes 1. Further, the wafer transfer arm 4 isrotatable in a θ-direction, as shown in FIG. 1, so that it can alsoaccess an alignment unit (ALIM) and an extension unit (EXT) that belongto the stacked units of a third group G3 of the process station 20, asdescribed later.

As shown in FIG. 1, the process station 20 has a main wafer transfermechanism 21 of the vertical transfer type located at the center andused as transfer means. The main wafer transfer mechanism 21 isaccommodated in a casing 22, around which all the processing units arestacked and divided into one or plurality of groups. In this embodiment,five groups G1, G2, G3, G4, and G5 each including stacked units arearranged. Of them, the stacked units of the first and second groups G1and G2 are located side by side on the front side of the system. Thestacked units of the third group G3 are located adjacent to the cassettestation 10. The stacked units of the fourth group G4 are locatedadjacent to the interface section 30. The stacked units of the fifthgroup G5 are located on the rear side.

As shown in FIG. 2, the first group G1 includes two processing unitsformed of a resist coating unit (COT) and a developing unit (DEV)stacked each other in the vertical direction in this order from below.The resist coating unit (COT) is arranged such that a predeterminedprocess is performed on a wafer W held on a spin chuck (not shown). Thedeveloping unit (DEV) is arranged such that developing solution supplymeans (not shown) is placed opposite to a wafer W within a container orprocess cup 23 to perform development of a resist pattern. The secondgroup G2 also includes two processing units formed of a resist coatingunit (COT) and a developing unit (DEV) stacked each other in thevertical direction in this order from below. The resist coating unit(COT) is located on the lower side, because the draining structure forthe resist liquid is complicated in terms of the mechanism andmaintenance. However, the resist coating unit (COT) may be located onthe upper side, as needed.

As shown in FIG. 3, the third group G3 includes processing units of theoven type stacked each other in the vertical direction, in each of whicha predetermined process is performed on a wafer W placed on a wafertable 24 (see FIG. 1). For example, the third group G3 includes eightprocessing units formed of, in this order from below, a cooling unit(COL) for cooling a wafer W; an adhesion unit (AD) for performing ahydrophobization process on a wafer W; an alignment unit (ALIM) forperforming alignment of a wafer W; an extension unit (EXT) fortransferring wafers W; and four hot plate units (HP) for baking a waferW. The fourth group G4 also includes processing units of the oven typestacked each other in the vertical direction. For example, the fourthgroup G4 includes eight processing units formed of, in this order frombelow, a cooling unit (COL); an extension and cooling unit (EXTCOL); anextension unit (EXT); a cooling unit (COL); two chilling hot plate units(CHP) having a rapid cooling function; and two hot plate units (HP).

As described above, the cooling unit (COL) and extension and coolingunit (EXTCOL), which use low process temperatures, are located on thelower side, while the hot plate unit (HP), chilling hot plate unit(CHP), and adhesion unit (AD), which use high process temperatures, arelocated on the upper side. Consequently, the thermal mutual interferencebetween these units can be suppressed. However, these units may bestacked each other at random.

As shown in FIG. 1, in the process station 20, ducts 25 and 26 arerespectively extended in the vertical direction in the sidewalls of thestacked units (processing units of the oven type) of the third andfourth groups G3 and G4, which are adjacent to the stacked units(processing units of the spinner type) of the first and second groups G1and G2. Clean air or air at a temperature specially adjusted is suppliedto flow through the ducts 25 and 26 as a downflow. This duct structureblocks off heat generated in the processing units of the oven type ofthe third and fourth groups G3 and G4, so that the heat does not affectthe processing units of the spinner type of the first and second groupsG1 and G2.

Further, in this processing system, the stacked units of the fifth groupG5 may be located on the rear side of the main wafer transfer mechanism21, as indicated by broken lines in FIG. 1. The fifth group G5 isarranged to be movable laterally relative to the main wafer transfermechanism 21 along a guide rail 27. Accordingly, even where the stackedunits of the fifth group G5 are set up, a space is formed by slidingthese units along the guide rail 27, so that a maintenance operation canbe easily performed on the main wafer transfer mechanism 21 from behind.

The interface section 30 has the same dimension as that of the processstation 20 in the depth direction, but has a smaller dimension in thewidth direction. The interface section 30 includes a buffer cassette 32of the stationary type and a pickup cassette 31 of the portable typestacked each other at two levels on the front side. The interfacesection 30 further includes a periphery light exposure unit 33 locatedon the rear side, which is light exposure means for performing lightexposure on the peripheral portion of a wafer W and light exposure onthe identification mark area thereof. The interface section 30 furtherincludes a wafer transfer arm 34 located at the center and used astransfer means. The transfer arm 34 is movable in the X- andZ-directions, so that it can transfer wafers to the two cassettes 31 and32 and periphery light exposure unit 33. Further, the wafer transfer arm34 is rotatable in a θ-direction, so that it can also transfer wafers tothe extension unit (EXT) in the stacked units of the fourth group G4 ofthe process station 20 and to a wafer transfer table (not shown) of thelight exposure apparatus adjacent thereto.

The processing system arranged as described above is installed in aclean room 40. Further, the cleanliness of the respective portionsinside the system is increased by an efficient laminar flow method.

Next, an explanation will be given of an operation of the resist liquidcoating/developing system described above.

At first, in the cassette station 10, wafer transfer arm 4 accesses acassette 1 that stores unprocessed wafers W on the cassette table 2, andtakes out a wafer W from the cassette 1. The wafer W thus taken out istransferred by the wafer transfer arm 4 to the alignment unit (ALIM) inthe stacked units of the third group G3 of the process station 20, andis placed on the wafer table 24 inside the unit (ALIM). The wafer Wplaced on the wafer table 24 is then subjected to orientation-flatalignment and centering operations. Thereafter, the main wafer transfermechanism 21 accesses the alignment unit (ALIM) from the opposite side,and receives the wafer W from the wafer table 24.

In the process station 20, the wafer W is first transferred by the mainwafer transfer mechanism 21 to the adhesion unit (AD) in the stackedunits of the third group G3. In the adhesion unit (AD), the wafer W issubjected to a hydrophobization process. After the hydrophobizationprocess is finished, the wafer W is transferred by the main wafertransfer mechanism 21 from the adhesion unit (AD) to the cooling unit(COL) in the stacked units of the third group G3 or fourth group and G4.In this cooling unit (COL), the wafer W is cooled to, e.g., 23° C.,which is a set temperature prior to a resist coating process. After thecooling process is finished, the wafer W is transferred by the mainwafer transfer mechanism 21 from the cooling unit (COL) to the resistcoating unit (COT) in the stacked units of the first group G1 or secondgroup G2. In this resist coating unit (COT), a resist is applied by aspin coating method onto the wafer W to form a film with a uniformthickness.

After the resist coating process is finished, the wafer W is transferredby the main wafer transfer mechanism 21 from the resist coating unit(COT) to one of the hot plate units (HP). In this hot plate unit (HP),the wafer W is placed on a table and is subjected to a pre-bakingprocess at a predetermined temperature of, e.g., 100° C. for apredetermined time. With this process, remaining solvent in the coatingfilm on the wafer W is removed by evaporation. After the pre-baking isfinished, the wafer W is transferred by the main wafer transfermechanism 21 from the hot plate unit (HP) to the extension and coolingunit (EXTCOL) in the stacked units of the fourth group G4. In this unit(EXTCOL), the wafer W is cooled to, e.g., 24° C., which is a temperaturesuitable for the next step, i.e., a periphery light exposure processperformed in the periphery light exposure unit 33. After this cooling isfinished, the wafer W is transferred by the main wafer transfermechanism 21 to the extension unit (EXT) immediately above the extensionand cooling unit (EXTCOL), and is placed on a table (not shown) insidethis unit (EXT). After the wafer W is placed on the table inside thisextension unit (EXT), the transfer arm 34 of the interface section 30accesses this unit from the opposite side and receives the wafer W.Then, the wafer W is transferred by the transfer arm 34 to the peripherylight exposure unit 33 in the interface section 30.

After the full face light exposure in the light exposure apparatus isfished and the wafer W is returned to the wafer transfer table on thelight exposure apparatus side, the transfer arm 34 of the interfacesection 30 accesses this wafer transfer table and receives the wafer W.Then, the wafer W is transferred by the transfer arm 34 to the extensionunit (EXT) in the stacked units of the fourth group G4 of the processstation 20, and is placed on a wafer transfer table inside this unit(EXT). Also, in this case, the wafer W may be temporarily placed in thebuffer cassette 32 of the interface section 30 before it is delivered tothe process station 20 side.

Then, the wafer W is transferred by the main wafer transfer mechanism 21from the wafer transfer table inside the extension unit (EXT) to thechilling hot plate unit (CHP). In the chilling hot plate unit (CHP), thewafer is subjected to a post exposure baking process for preventingfringe generation or for inducing an acid catalyst reaction for achemical amplification type resist (CAR).

Thereafter, the wafer W is transferred to the developing unit (DEV) inthe stacked units of the first group G1 or second group G2. In thisdeveloping unit (DEV), a developing process is performed while adeveloping solution is supplied all over the resist on the surface ofthe wafer W. With this developing process, the resist film formed on thesurface of the wafer W is developed to have a predetermined circuitpattern. In addition, an unnecessary part of the resist film is removedfrom the peripheral portion of the wafer W. Further, a part of theresist film is removed from the area of an alignment mark M formed(applied) on the surface of the wafer W. After the developing process isfinished, a rinsing liquid is supplied onto the surface of the wafer Wto wash out the developing solution.

After this development step is finished, the wafer W is transferred bythe main wafer transfer mechanism 21 from the developing unit (DEV) toone of the hot plate units (HP) in the stacked units of the third groupG3 or fourth group G4. In this unit (HP), the wafer W is subjected to apost baking process at a temperature of, e.g., 100° C. for apredetermined time. With this process, the resist swelled by thedevelopment is cured and is thereby improved in the chemical resistance.

After the post baking is finished, the wafer W is transferred by themain wafer transfer mechanism 21 from the hot plate unit (HP) to one ofthe cooling units (COL). In this cooling units (COL), the wafer W iscooled to room temperature. Then, the wafer W is transferred by the mainwafer transfer mechanism 21 from the cooling units (COL) to theextension unit (EXT) in the third group G3. After the wafer W is placedon a table (not shown) inside this extension unit (EXT), the wafertransfer arm 4 of the cassette station 10 accesses this unit from theopposite side and receives the wafer W. Then, the wafer W is transferredby the wafer transfer arm 4 and is inserted into a predetermined waferreceiving groove in a cassette 1 for storing processed wafers on thecassette table 2. As a result, the process is completed.

Next, an explanation will be give of the structure of the resist coatingunit shown in FIG. 1. The resist coating/developing system includes tworesist coating units of the same type. Specifically, they are a firstprocessing unit 41 (first coating unit 41) of the spinner type belongingto the first group G1 and a second processing unit 42 (second coatingunit 42) of the spinner type belonging to the second group G2. Each offirst and second coating units 41 and 42 includes a process chamber 43,which has a transfer port 45 formed adjacent to the main wafer transfermechanism 21 and provided with a shutter 44 for opening/closing the port45. The process chamber 43 further has a maintenance opening 47 formedon the outer side (the lower side in FIG. 1) and provided with a coverdoor 46 for opening/closing the opening 47.

FIG. 4 shows a specific structure of the first and second coating units41 and 42. Each of first and second coating units 41 and 42 includes acasing 48, in which a spin chuck 49, a process cup 23, and a complexnozzle 50 are arranged. The spin chuck 49 serves as holding means forholding a wafer W to be rotatable. The process cup 23 surrounds the spinchuck 49, wafer W, and portions therebelow. The complex nozzle 50 cansupply process liquids or coating liquids, such as a resist liquid and asolvent, onto the surface of the wafer W.

The spin chuck 49 includes a chuck plate 49 a attached at the top of arotary shaft 52 to be rotated by a spin motor 51 located on the lowerside in the casing 48. The chuck plate 49 a is provided with a holdingmember (not shown) vertically extending from the peripheral edge. Theholding member is configured to hold the peripheral edge of the wafer Wsuch that the wafer W is separated above from the chuck plate 49 a.

The atmosphere inside the process cup 23 is exhausted through the bottomof the process cup 23 by exhaust means, such as a vacuum pump, locatedoutside. Further, part of a process liquid scattered by rotation of thewafer W is exhausted from around the spin chuck 49 into the drain 28located at the bottom of the process cup 23. The process cup 23 ismovable up and down, and is detachable for maintenance, as needed.

The complex nozzle 50 is attached to the top of the swing arm 54 servingas a traveling member that swings about a pivot shaft 53. The complexnozzle 50 includes a coating liquid supply nozzle 56 connected to acoating liquid supply conduit 55 and configured to deliver a coatingliquid, and a solvent supply nozzle 58 connected to a solvent supplyconduit 57 and configured to deliver a solvent. These nozzles 56 and 58are located above the wafer W side by side in radial direction of thewafer W, and are opened on the lower face of the complex nozzle 50.Specifically, the coating liquid supply nozzle 56 and solvent supplynozzle 58 arrayed side by side with a predetermined gap therebetweensuch that the coating liquid supply nozzle 56 is positioned on the innerside and the solvent supply nozzle 58 is positioned on the outer side inradial direction of the wafer W. A coating liquid is supplied from thecoating liquid supply conduit 55 to the coating liquid supply nozzle 56.A solvent is supplied from the solvent supply conduit 57 to the solventsupply nozzle 58. The coating liquid and solvent are then deliveredindependently of each other from these nozzles 56 and 58.

As shown in FIG. 4, the swing arm 54 is fixed in a horizontal state atthe top of the pivot shaft 53, which vertically extends outside theprocess cup 23. The swing arm 54 is swung in a horizontal plane by arotary mechanism 59 (nozzle shifting mechanism 59) connected to thepivot shaft 53. The swing arm 54 can be moved above the wafer W betweena position near the center of the wafer W and a waiting position (homeposition) outside the process cup 23. During a process for forming acoating film T on the wafer W, the swing arm 54 is moved between thesepositions.

Next, an explanation will be given of a control system used forreplacing the process cup.

The shutter 44 on the transfer port 45 of the process chamber 43 isarranged to be moved up and down by an opening/closing driving mechanism60, such as a cylinder, to open/close the transfer port 45. In order todetect the shutter 44 being opened/closed, a shutter opening/closingsensor 61 of, e.g., the optical type is located near the shutter 44 tooutput a detection signal when the shutter 44 is opened. Further, inorder to detect door-interlocking for the cover door 46, a door switch62 is located at the edge of the maintenance opening 47.

The shutter opening/closing sensor 61 and door switch 62 are connectedto an input of a control computer 63 serving as control means. Theprocessing apparatus described above is preset to be controlled byprocess sequences stored in this control computer 63 in advance.

As schematically shown in FIG. 1, the control computer 63 includescontrol means 64 formed of a central processing unit (CPU) serving as amain body (the control means 64 will be referred to as a CPU 64). Thecontrol computer 63 further includes an I/O (input/output) section 65connected to the CPU 64, a display section 66 arranged to display theimage pictures concerning an input process sequence to fabricate theprocess sequence, and a storage medium 67, which stores a controlsoftware, attached to the I/O section 65. As shown in FIG. 2, thecontrol computer 63 is placed on the cassette table 2 of the cassettestation 10. In this embodiment, the control computer 63 comprises theI/O section 65 formed of a retractable keyboard of the pullout type, thedisplay section 66, and the storage medium 67.

The storage medium 67 may be a medium stationary in the control computer63, or a medium detachably attached to and read by a reading deviceprovided in the control computer 63. In the most typical case, thestorage medium 67 is formed of a hard disk drive with control softwareinstalled therein by a service man of the maker of this substrateprocessing apparatus. In another case, the storage medium 67 is formedof a reading only removable disk, such as a CD-ROM or DVD-ROM, with acontrol software stored therein. A removable disk of this kind is readby an optical reading device provided in the control computer 63. Thestorage medium 67 may be any one of the RAM (random access memory) andROM (read only memory) types. Further, the storage medium 67 may be aROM of the cassette type. In other words, the storage medium 67 can beformed of an any one of the storage media known in the technical filedof computers.

The control computer 63 arranged as described above executes a controlsoftware to perform control for realizing the following functions.Specifically, one of the functions is an interlock mechanism (door lockcircuit) to essentially stop the processing apparatus when the coverdoor 46 is opened. Another function is an interlock mechanism toprohibit an operation of the transfer means or transfer arm 34 when theshutter 44 is closed. Another function is a special control function,for example, to stop the spin motor when the cup is replaced. Further,the control computer 63 performs ordinary control for realizing variousprocess conditions defined by a predetermined process sequence for therespective functional components of the processing system, such asoperations of the main wafer transfer mechanism 21 and spin chuck 49,and supply and stop of the coating liquid and solvent from the nozzles56 and 58.

In this embodiment, a program for replacing the process cup 23 inaccordance with the flow shown in FIG. 5 is stored in advance in thestorage medium 67 of the control computer 63. The control computer 63controls the transfer arm 34 to transfer wafers W based on this processprogram.

Next, an explanation will be given of a method for replacing the processcup 23 with reference to FIG. 5.

(1) A case where all the coating units are designated as cup replacementtarget processing units.

This cup replacement process will be explained in a case where aprocessing apparatus includes one or a plurality of processing units ofthe same type (for example, a coating unit), and in considerationfurther of a process performed in another processing unit (for example,a developing unit).

Where the process cups 23 of all the coating units of the same type arereplaced, the processing apparatus cannot keep performing a sequentialprocess. In light of this, appointment registrations (preset) for thereplacement target processing units are made in advance in the CPU 64.Accordingly, in the flow shown in FIG. 5, it is first judged whether theprocess cup replacement is directed to all the processing units (orunit), with reference to the type and number of the processing unitsinstructed by an operator or known by stored data (Step S101).

Where this process cup replacement is directed to all the processingunits (or unit) (Yes at Step S101) e.g., it is directed to theprocessing units of the same type, such as the coating units 41 and 42,an instruction to set takeoff suspension of the next lot is sent to thecassette station 10 serving as a carry-in section (Step S102).

Then, it is checked whether the process on the last wafer W is finishedin the cup replacement target processing units (the first and secondcoating units 41 and 42) (Step S104). Where a wafer W in process remains(No at Step S104), the flow waits until the process on the last wafer Wis finished (Step S104).

When the process on the last wafer W is finished in the replacementtarget processing units (the finish timing may be not single whereprocesses are performed in the processing units in parallel), the CPU 64informs an operator that a replacing operation of the process cups 23 ispermitted (Step S105). Then, the flow waits until the shutter 44 on thetransfer port 45 of each of the processing units is closed by anoperator (Step S106).

When the shutter 44 is closed, the interlock mechanism 69 is therebyactivated in general. In light of this, operation prohibition applied tothe transfer means by the interlock mechanism 69 is set disabled (StepS107). Consequently, the main wafer transfer mechanism 21 is allowed toperform a load/unload operation relative to a processing unit notdesignated as a process instrument replacement target.

After this state is established, the cover door 46 is opened and a cupreplacing operation is performed by an operator (Step S108). At thistime, a shutter lock (not shown) is operated by the operator to preventthe shutter 44 from being mechanically opened.

After the cup replacing operation is finished, the operation prohibitionapplied to the main wafer transfer mechanism 21 by the interlockmechanism 69 is re-set enabled (Step S109). Then, an instruction tocancel the takeoff suspension of the next lot is sent to the cassettestation 10, serving as a carry-in section (Steps S109 to S110), therebycompleting the flow.

According to this method for replacing the process cups 23, it ispossible to prevent takeoff of the next lot from the carry-in section.

(2) A case where a cup replacement target processing unit is solelyconsidered.

This is a case where the first coating unit 41 is designated as a cupreplacement target processing unit, and control is performed withoutreference to the processes performed in the other processing units (forexample, the second coating unit 42 and developing unit). In this case,the cup replacement process flow shown in FIG. 5 is modified to excludeSteps S101 to S103 and Steps S109 to S110.

In this case, an appointment registration (preset) for the cupreplacement target processing unit (first coating unit 41) is made inadvance in the CPU 64. Then, it is checked by the CPU 64 whether a waferin process is present in the cup replacement target processing unit(first coating unit 41), i.e., the process on the target object isfinished (Step S104). Where a wafer W in process remains (No at StepS104), the flow waits until the process on the last wafer W is finished(Step S104).

When the process on the last wafer W is finished, and the wafer W isunloaded from the processing unit (first coating unit 41), the CPU 64informs an operator by use of an alarm unit 68 (see FIG. 1) that a cupreplacing operation of the process cup 23 is permitted (Step S105).Then, it is confirmed whether the shutter 44 on the transfer port 45 ofthe processing unit (first coating unit 41) is closed by an operator(Step S106). The shutter 44 being closed is detected by the CPU 64 thatobserves the output of the shutter opening/closing sensor 61. After theshutter 44 is closed, the cover door 46 is opened to perform maintenanceof the process cup 23.

When the cover door 46 is opened, the interlock mechanism 69 (see FIG.5) is thereby activated in general, and an operation prohibition stateis applied to the transfer means or main wafer transfer mechanism 21. Inlight of this, operation prohibition applied to the main wafer transfermechanism 21 by the interlock mechanism 69 is set disabled (Step S107).Consequently, the main wafer transfer mechanism 21 is allowed to performa load/unload operation relative to a processing unit not designated asa process instrument replacement target.

After this state is established, a cup replacing operation is performedby an operator through the maintenance opening 47 with the cover door 46opened (Step S108). At this time, a shutter lock (not shown) is operatedby the operator to prevent the shutter 44 from being mechanicallyopened. The cover door 46 being opened is detected by the CPU 64 thatobserves the output of the door switch 62.

After the cup replacing operation is finished, the operation prohibitionapplied to the main wafer transfer mechanism 21 by the interlockmechanism 69 is re-set enabled (Step S109), thereby completing the flow.

According to this method for replacing the process cups 23, where awafer W in process is present in the cup replacement target processingunit, the end of the process is used as a time point to provideinformation that process cup replacement is permitted. Accordingly, itis possible for an operator to immediately close the shutter 44 and openthe cover door 46 to start an cup replacing operation.

(3) A case where one of a plurality of processing units is designated asa cup replacement target.

This is a case where a processing apparatus includes a plurality ofprocessing units of the same type (coating units), and one of them isdesignated as a process cup replacement target. In this case, a presentcoating process can be continued by use of another processing unit ofthe same type as the cup replace target processing unit.

At first, in the flow shown in FIG. 5, it is first judged whether theprocess cup replacement is directed to all the processing units, withreference to the type and number of the processing units instructed byan operator or known by stored data (Step S101). Where this process cupreplacement is directed to not all the processing units (No at StepS101), e.g., it is directed to one of the processing units of the sametype (coating units), (in this embodiment, two units formed of the firstcoating unit 41 and second coating unit 42), a change is made in thetransfer schedule registered for the normal operation including no cupreplacement appointment. Specifically, the transfer schedule for thenext lot is changed by the CPU 64, based on a cup replacementappointment registration (preset), to avoid use of the cup replacementtarget processing unit (Step S103).

Then, it is checked whether the process on the target object is finishedin the cup replacement target processing unit (the first coating unit41) (Step S104). Where a wafer W in process remains (No at Step S104),the flow waits until the process on the last wafer W is finished (StepS104).

When the process on the last wafer W is finished, an operator isinformed that a replacing operation of the process cup 23 is permitted(Step S105). Then, the flow waits until the shutter 44 on the transferport 45 of the processing unit is closed by an operator (Step S106).

When the shutter 44 is closed, the interlock mechanism 69 is therebyactivated in general. In light of this, operation prohibition applied tothe main wafer transfer mechanism 21 by the interlock mechanism 69 isset disabled (Step S107). Consequently, the main wafer transfermechanism 21 is allowed to perform a load/unload operation relative to aprocessing unit not designated as a process instrument replacementtarget.

After this state is established, the cover door 46 is opened and a cupreplacing operation is performed by an operator (Step S108). At thistime, a shutter lock (not shown) is operated by the operator to preventthe shutter 44 from being mechanically opened.

After the cup replacing operation is finished, the operation prohibitionapplied to the main wafer transfer mechanism 21 by the interlockmechanism 69 is re-set enabled (Step S109), thereby completing the flow.

According to this method for replacing the process cup 23, although thethroughput of the coating process is decreased, it is possible tocontinue a present process on target objects, such as a developingprocess including a coating process, and a heating process, only with achange in the transfer schedule.

Specific Example

Next, a detailed explanation will be given of a specific example of amethod for replacing a process cup 23 according to the presentinvention, with reference to FIGS. 4 and 6 to 8.

At first, a cup replacement appointment is made for a processing unitwith a process cup 23 to be replaced (in this case, one of the firstcoating unit 41 and second coating unit 42) designated by an operatorthrough the I/O section 65 of the control computer 63 with reference tothe view of operational image pictures shown on the display section 66.At this time, changes are made in terms of the takeoff suspension of thenext lot and the transfer schedule for the next lot.

As shown in FIG. 6, it is checked by the CPU 64 whether a cupreplacement appointment is present (Step S1). Where a cup replacementappointment is present (Yes at Step S1), an alarm for “presence of cupreplacement appointment” is indicated by cup replacement progressindicator 70 (see FIG. 4) of the alarm unit 68 or the display section 66(see FIGS. 2 and 4) (Step S2).

Then, it is judged whether the process cup replacement is directed toall the coating units (or unit), with reference to the content of thecup replacement appointment (Step S3).

Where the process cup replacement is directed to not all the processingunits (No at Step S3), e.g., it is directed to one of the processingunits of the same type (coating units), (in this embodiment, two unitsformed of the first coating unit 41 and second coating unit 42), thetransfer schedule for the next lot is changed to avoid use of the cupreplacement target processing unit (Step S4).

On the other hand, where the process cup replacement is directed to allthe processing units (or unit) (Yes at Step S3), e.g., it is directed tothe sole processing unit (first coating unit 41) of the type designatedas a replacement target processing unit, an instruction to set takeoffsuspension of the next lot is sent to the cassette station 10 serving asa carry-in section (Step S5).

Then, it is checked whether the process on a wafer W is finished in thecup replacement target, i.e., first coating unit 41, (Step S64). Where awafer W in process remains (No at Step S6), the flow waits until theprocess on the last wafer is finished and the wafer is unloaded from thefirst coating unit 41 (Step S6).

When the process on the last wafer W is finished, a cup replacementpermission indicator 71 of the alarm unit 68 (see FIG. 4) is activatedby the CPU 64 to show an alarm to provide an operator with informationthat a replacing operation of the process cups 23 is permitted (StepS7). Then, an LED 73 built in a cup replacement switch 72 (see FIG. 4)of the cup replacement target, i.e., first coating unit 41, is blinked(Step S8). An operator can push the cup replacement switch 72 inresponse to the LED 73 being blinked.

Then, as shown in FIG. 7, it is checked by the CPU 64 whether the cupreplacement switch 72 has been turned on (Step S9). Where the cupreplacement switch 72 is in the ON-state (Yes at Step S9), the cupreplacement progress indicator 70 of the alarm unit 68 is activated toshown an alarm for cup replacement in progress (Step S10), and the LED73 built in the cup replacement switch 72 is turned on (Step S11).

Then, it is confirmed whether the shutter 44 is closed (Step 12). Wherethe shutter 44 is not closed (No at Step 12), an instruction to closethe shutter 44 is provided (Step 13).

Where the shutter 44 is closed (Yes at Step S12), the interlockmechanism 69 (see FIG. 5) is thereby activated in general. In light ofthis, the interlock mechanism 69 is set disabled, so that an operationprohibition state applied to the main wafer transfer mechanism 21 iscancelled (Step S14). Further, an interlock mechanism disablementindicator 75 (see FIG. 5) is activated to provide information about thisdisablement (Step S15). Consequently, the main wafer transfer mechanism21 is allowed to perform a load/unload operation relative to aprocessing unit not designated as a process instrument replacementtarget.

Then, a door lock circuit 76 (see FIG. 4) serving as an interlockmechanism for the cover door 46 is set disabled (Step S16). Further, adoor lock circuit disablement indicator 77 (see FIG. 4) is activated togenerate an alarm for this disablement of the door lock circuit (StepS17). Consequently, even where the cover door 46 is opened, theprocessing apparatus is not stopped, and thus it can continue anoperation. Then, the operation of the spin motor 51 (see FIG. 4) isfurther prohibited for the safety (Step S18).

Thereafter, an objective replacing operation of the process cup 23 isstarted by an operator (Step S19). After this replacing operation isfinished, the cup replacement switch 72 is pushed again by an operatorto turn off the cup replacement switch 72.

Then, as shown in FIG. 8, when the cup replacement switch 72 is turnedoff (Yes at Step S20), the interlock mechanism 69 is re-set enabled bythe CPU 64 to work on the main wafer transfer mechanism 21 (Step S21).Further, the alarm for disablement of the interlock mechanism 69 iscleared (Step S22). In addition, the door lock circuit 76 is re-setenabled, and the alarm for disablement of the door lock circuit iscleared (Steps S23 and S24). The operation of the spin motor 51 is alsore-set enabled (Step S25). Then, the alarm for cup replacement inprogress is cleared (Step S26). Further, the LED 73 of the cupreplacement switch 72 is turned off (Step S27).

As described above, where the first coating unit 41 is the sole unit, aninstruction to set takeoff suspension of the next lot is used. In thiscase, at the end, an instruction to cancel the takeoff suspension of thenext lot is sent to the cassette station 10 serving as a carry-insection (Steps S28 to S29).

According to the cup replacement process described above, (1) wherereplacement of a process cup 23 is directed to all the processing units(or unit) registered on the transfer schedule, (a) when a cupreplacement appointment is made, takeoff suspension of the next lot isset, and (b) a process on the next lot is restarted after the cupreplacement for all the processing units is finished. Further, (2) wherereplacement of a process cup 23 is directed to part of the processingunits registered on the transfer schedule, (a) when a cup replacementappointment is made, the transfer schedule for the next lot and furthersubsequent lots is changed to avoid use of the cup replacement targetprocessing unit, thereby continuing a lot process, and (b) when the cupreplacement is finished, the transfer schedule for further subsequentunprocessed lots is changed to use all the modules, thereby continuingthe process.

Incidentally, in the embodiment described above, a replacement targetprocessing unit is exemplified by a coating unit having a process cup23. However, the present invention is not limited to this embodiment,and it may be applied to a case where another process instrument usedfor a process, such as a nozzle 56 or 58, spin chuck 49, or filter, isreplaced or inspected.

1. A non-transitory storage medium that stores a program for executionon a computer to perform a process instrument replacement in aprocessing apparatus, in which target objects are loaded by a transfermechanism into processing units and are processed therein, wherein theprogram causes the computer to execute: confirming that a process on thetarget object is finished in a designated one of the processing unitsdesignated to replace a process instrument attached therein, andproviding information that a process instrument replacing operation ispermitted to start; and, when the designated processing unit is set in amaintenance preparatory state to perform the process instrumentreplacing operation and an operation prohibition state is therebyapplied to the transfer mechanism, canceling the operation prohibitionstate to allow the transfer mechanism to perform a load or unloadoperation of a target object relative to a processing unit notdesignated to replace a process instrument attached therein.
 2. Thestorage medium according to claim 1, wherein the operation prohibitionstate applied to the transfer mechanism is made by an interlockmechanism in response to a shutter of a target-object load port of thedesignated processing unit being closed.
 3. The storage medium accordingto claim 2, wherein the program causes the computer to further executeenabling the operation prohibition state applied to the transfermechanism by the interlock mechanism, in response to the processinstrument replacing operation being finished.
 4. The storage mediumaccording to claim 1, wherein the maintenance preparatory state includesa state where a maintenance door of the designated processing unit isopen.
 5. The storage medium according to claim 1, wherein the designatedprocessing unit is a resist coating unit and the process instrument is acup surrounding a coating process field in the designated processingunit.
 6. The storage medium according to claim 1, wherein a plurality ofthe processing units are designated processing units designated toreplace a processing instrument therein, and said providing informationthat a process instrument replacing operation is permitted to start isperformed after a last target object process is finished in theplurality of designated processing units.
 7. The storage mediumaccording to claim 6, wherein the plurality of designated processingunits are configured to perform the same process.
 8. A non-transitorystorage medium that stores a program for execution on a computer toperform process instrument replacement in a processing apparatus, inwhich target objects from a carry-in section are loaded by a transfermechanism into processing units and are processed therein, and thetarget objects thus processed are unloaded by a transfer mechanism to acarry-out section, wherein the program causes the computer to execute:setting a process instrument replacement appointment for a designatedprocessing unit designated to replace a process instrument attachedtherein; setting takeoff suspension of a next lot of target objects fromthe carry-in section to the designated processing unit, in response tothe appointment being set, before starting a process instrumentreplacing operation; confirming that a process on the target object isfinished in the designated processing unit, and providing informationthat the process instrument replacing operation is permitted to start;when the designated processing unit designated is set in a maintenancepreparatory state to perform the process instrument replacing operationand an operation prohibition state is thereby applied to the transfermechanism, canceling the operation prohibition state to allow thetransfer mechanism to perform a load or unload operation of a targetobject relative to a processing unit not designated to replace a processinstrument attached therein; and canceling the takeoff suspension of thenext lot of target objects from the carry-in section to the designatedprocessing unit, in response to the process instrument replacingoperation being finished.
 9. The storage medium according to claim 8,wherein the operation prohibition state applied to the transfermechanism is made by an interlock mechanism in response to a shutter ofa target-object load port of the designated processing unit beingclosed.
 10. The storage medium according to claim 9, wherein the programcauses the computer to further execute enabling the operationprohibition state applied to the transfer mechanism by the interlockmechanism, in response to the process instrument replacing operationbeing finished.
 11. The storage medium according to claim 8, wherein themaintenance preparatory state includes a state where a maintenance doorof the designated processing unit is open.
 12. The storage mediumaccording to claim 8, wherein the designated processing unit is a resistcoating unit and the process instrument is a cup surrounding a coatingprocess field in the designated processing unit.
 13. A non-transitorystorage medium that stores a program for execution on a computer toperform process instrument replacement in a processing apparatus, inwhich target objects from a carry-in section are loaded by a transfermechanism into processing units and are processed therein, and thetarget objects thus processed are unloaded by the transfer mechanism toa carry-out section, the processing units including predeterminedprocessing units configured to perform the same process and wherein theprogram causes the computer to execute: setting a process instrumentreplacement appointment for a designated processing unit designated toreplace a process instrument attached therein among the predeterminedprocessing units; changing a transfer schedule for transferring targetobjects, preset prior to the appointment, into a transfer schedulearranged to avoid use of the designated process unit among thepredetermined processing units; confirming that a process on the targetobject is finished in the designated processing unit, and providinginformation that a process instrument replacing operation is permittedto start; and, when the designated processing unit is set in amaintenance preparatory state to perform the process instrumentreplacing operation and an operation prohibition state is therebyapplied to the transfer mechanism, canceling the operation prohibitionstate to allow the transfer mechanism to perform a load or unloadoperation of a target object relative to a processing unit notdesignated to replace a process instrument attached therein.
 14. Thestorage medium according to claim 13, wherein a plurality of theprocessing units are designated processing units designated to replace aprocessing instrument therein, and said providing information that aprocess instrument replacing operation is permitted to start isperformed after a last target object process is finished in theplurality of designated processing units.
 15. The storage mediumaccording to claim 13, wherein the operation prohibition state appliedto the transfer mechanism is made by an interlock mechanism in responseto a shutter of a target-object load port of the designated processingunit being closed.
 16. The storage medium according to claim 15, whereinthe program causes the computer to further execute enabling theoperation prohibition state applied to the transfer mechanism by theinterlock mechanism, in response to the process instrument replacingoperation being finished.
 17. The storage medium according to claim 13,wherein the maintenance preparatory state includes a state where amaintenance door of the designated processing unit is open.
 18. Thestorage medium according to claim 13, wherein the program causes thecomputer to further execute setting takeoff suspension of a next lot oftarget objects from the carry-in section to the designated processingunit, in response to the appointment being set, before starting theprocess instrument replacing operation, and canceling the takeoffsuspension of the next lot of target objects from the carry-in sectionto the designated processing unit, in response to the process instrumentreplacing operation being finished.
 19. The storage medium according toclaim 13, wherein the designated processing unit is a resist coatingunit and the process instrument is a cup surrounding a coating processfield in the designated processing unit.